What breed is my roo?

We got this roo as a week-old chick from a lady who breeds French Black Copper Marans and has a mixed barnyard flock (including several barred rock). His legs are yellow and feathered all the way down his outside toe. He's 6.5 months old and loves the ladies. A friend suggested he might be a Cuckoo Marans, but the yellow legs are wrong. I'd love to hear what you all think.